Bulk acoustic wave (BAW) and surface acoustic wave (SAW) devices have been fabricated for decades using traditional semiconductor integrated circuit methods. These methods are mature and optimized to produce >1 billion high fidelity, matched filters for RF and microwave communications such as cell phones, walkie-talkies, and other devices. However, relatively sophisticated and expensive equipment is required to produce these devices.
High performance acoustic wave structures have recently been exploited for sensor applications. Acoustic wave structures have been demonstrated to perform as temperature, strain and hydrogen sensing devices, employing traditional photo-lithography for device fabrication. Photo-lithography is time consuming and comparatively expensive, and accordingly new methodologies for manufacturing such sensors are necessary.